"If we looked at all 470 (bailout) recipients, how much would they owe?" said Georgia Rep. John Lewis, who chairs the subcommittee overseeing the bailouts.

A thorough review of all participating firms is warranted.

Those companies had to sign contracts stating they had no unpaid taxes. Neil Barofski, special inspector general for the TARP bailout program, said lying on those document could be a crime. He said his office will probe the matter, and it should.

But Congress also should probe whether the U.S. Treasury checked the firms' tax records. Americans deserve to know whether Treasury, which green-lighted unjustifiable bonuses at AIG, also fell asleep at the wheel on this one.